Dragon Tech WS-100 In-Wall Light Switch

Posted January 3, 2017

Dragon Tech WS-100 In-Wall Light Switch

The build quality of the Dragon Tech WS-100 Z-Wave light switch is comparable to that of the more expensive brands. The first thing I noticed about the Dragon Tech switch was the thickness of the metal yoke or mounting strap. This sturdy yoke means that once mounted, there is no noticeable flexing sensation when operating the Dragon Tech switch. The rocker-style paddle of the WS-100 has a solid feel, with a distinct up-position and down-position. Unlike some other brands there is no additional “inclusion” button on the front panel, nor are there any odd gaps or recesses – all prone to collecting dust and grime.

The screw terminals on the back of the WS-100 will accommodate 14-gauge and larger wires, and there are also holes for 14-gauge wires. Again I noticed the ruggedness of this switch as I tightened down the screw terminals.

A couple of notes about wiring: Although the instructions indicate that the wire holes are intended for 14-gauge wire, I was able to fit a stripped 12-gauge wire into one of the holes. However, I think best practice is to have the insulation extend slightly into the hole, leaving no energized metal exposed on the back of the switch. The insulation on a 12-gauge wire would not fit into the hole. Also it is not a good idea to mix gauges when using the wire holes. The nut inside will snug down against the thicker wire before it comes in contact with the thinner wire, and the thinner wire will pull right out.

One minor complaint that I had about the wiring connections was that the green paint coating on the grounding screw was a bit thicker that the anodized green coating usually found on grounding screws. The thicker paint tended to bind when tightening the screw.

My only real complaint when wiring the Dragon Tech switch was in regard to the wiring diagrams in the documentation. The diagrams show the grounding screw being located on the downward edge of the switch:

I followed the diagrams and mounted the switch with the grounding screw facing down. That turned out to be upside-down: the “Up” on the rocker switch became “Off” and “Down” became “On.” Granted there’s a Z-Wave configuration parameter for reversing the operation of the switch, but rather than change the default operation of the switch, I opted to remount the switch. The proper way to mount the switch is with the text of the mounting strap appearing right-side-up. Here’s a photo showing the ground screw on top relative to the text engraved on the front of the mounting strap:

Installing the Dragon Tech switch in a three-way application, using the WA-100 companion switch was a bit more challenging. According to the multiway switching article at Wikipedia.org, there are several wiring configurations that may be encountered when working with an existing installation. A typical three-way arrangement using single-pole, double-throw (SPDT) switches might be diagrammed as follows:

In practice however, the hot and neutral wires from the breaker panel could have been brought out to any of the three junction boxes in the three-way circuit, and there’s a possibility that you won’t get both the hot and the neutral wires together in either of the two switch boxes. The Dragon Tech WS-100 switch definitely needs both a hot and a neutral in its box, and the “companion” Dragon Tech WA-100 Three-Way Auxiliary Switch also requires a neutral (usually white) wire in its box. If there isn’t a neutral in each of the two boxes, that may prove to be a deal-breaker, unless there is an unused wire in the box that can be used to bring in a neutral.

Another obstacle in any three-way Z-Wave installation is that the wire to the load also needs to be in the same junction box as the “smart” half (WS-100) of the Z-Wave switch pair. In my case the load wire was in the other junction box where I planned to mount the WA-100 companion switch. That’s usually the case in any three-way installation: you’ll have the wire to the load located in one box, and you’ll have the hot wire from the breaker panel in the other box. That obstacle can be resolved by using one of the “traveling” wires between the two boxes to route the load wire back to the smart switch.

The included documentation reminds the installer to shut off the breaker to the three-way circuit before beginning the installation and to label all of the wires connected to the two switches before starting to disconnect anything. After removing the old switches, identify the two “traveling” wires that ran between those switches. The two traveling wires will be the wires that were not connected to the common terminal or to the ground terminal of the old switches. One traveling wire may be red, and one may be black, but rather than relying on the colors being correct, I like to use an Ohmmeter to check continuity from one end of each wire to the other end.

With the two old traveling wires identified, we will reuse one of the two wires as our new traveler as shown in the Dragon Tech documentation, and the other wire can either be used to bring the load connection from the companion switch’s box back into the “smart” switch’s box, or to bring a neutral connection from the smart switch’s box into the companion switch’s box. Use a wire nut to make the appropriate splice connections.

After restoring power to the circuit, I was delighted to discover that “Up” on either the WS-100’s paddle or the companion switch’s paddle resulted in “On” and “Down on either switch’s paddle resulted in “Off.” It’s not like the old-style three-way switches in which one switch being left in the “wrong” state reverses the operation of the other switch.

Inclusion into the Z-Wave network was effortless and flawless. I observed the system controller logs during the inclusion process and noted that the Dragon Tech switch informed the system controller that it was Z-Wave Plus certified, and then it went on to perform the handshaking required by Plus-certified devices, including notifying the system controller of its capabilities.

Unlike Leviton and Cooper switches, the Dragon Tech switch has to be polled by the system controller in order to discover its on/off state whenever the switch is operated manually. The real-time notification capability of Leviton and Cooper switches is protected by a patent, which may explain why those switches are more expensive. Update: supposedly the patent restrictions on instant notification expire in February 2016, and since the WS-100 supports over-the-air firmware updating, there is a possibility that the Dragon Tech switch can be upgraded by the end-user to enable instant notification. Ask your Dragon Tech vendor about the availability of firmware updates.

The Dragon Tech WS-100 has two parameters that can be configured via Z-Wave:

Parameter 4, when set to its default value of 0, will result in “Up” turning the light on and “Down” turning the light off. Setting this parameter to 1 reverses the up and down functions.

Parameter 3, when set to its default value of 0 causes the LED on the front panel to act in nightlight/locator mode, with the LED on when the lights are off. Setting this parameter to 1 causes the LED to be on when the lights or on. Setting the parameter to 2 disables the LED.

The Dragon Tech documentation includes instructions on how to change the face-plate, and I understand that color change kits for the Dragon Tech switches will soon be available.

I highly recommend the Dragon Tech WS-100 In Wall Z-Wave Light Switch. If you don’t mind polling for status, the Dragon Tech offers the same quality of the more expensive brands at a much lower price.